What Are the First Signs of Perimenopause?

The first signs of perimenopause are most commonly changes to your menstrual cycle: periods that become irregular, heavier, lighter, or closer together than usual. Alongside this, many women notice sleep disruption, mood shifts, brain fog, and in some cases hot flushes, often before they realise these symptoms are connected to hormonal change. Perimenopause typically begins in the mid-to-late 40s in Australia, though for some women it starts in the late 30s.

If you are wondering whether what you are experiencing is perimenopause, this guide walks through the 11 most common early signs and what to do if you recognise them, in plain language without the jargon. For a fuller reference on the full range of symptoms across the whole transition, see our guide to perimenopause symptoms.

What is perimenopause?

In plain terms: perimenopause is the transitional stage leading up to menopause, the point confirmed after 12 consecutive months without a period. It is driven by gradually declining and fluctuating oestrogen as the ovaries begin to wind down. In Australia the average age of menopause is 51 to 52, which means perimenopause typically spans the mid-to-late 40s, though the timeline varies significantly between women. It is a normal biological process, not a medical condition.

The word literally means “around menopause.” Menopause itself is technically a single moment in time: the point at which you have gone 12 months without a period. Everything leading up to that point, which can span several years, is perimenopause. On average it lasts four to six years, but it can be as short as a few months or as long as a decade.

What makes perimenopause particularly confusing is that your hormone levels do not decline in a smooth, predictable line. They fluctuate, sometimes dramatically, which is why your symptoms can feel inconsistent and hard to pin down. You might feel completely fine for weeks, then have a stretch where everything hits at once.

What are the signs of perimenopause? 11 things to watch for

Not every woman will experience all of these, and the severity varies enormously from person to person. Research from Jean Hailes for Women’s Health indicates that around 80 per cent of Australian women experience some perimenopausal symptoms, with roughly 20 per cent describing them as severe enough to significantly affect daily life. Symptoms can begin years before periods stop entirely, which is why many women are surprised to find they are already in perimenopause when they first seek answers.

1. Irregular periods

This is usually the first and most telling sign. Your cycle may become shorter, longer, heavier, lighter, or simply unpredictable from month to month. You might skip a period entirely, then have two close together.

2. Hot flushes

A sudden wave of heat, usually starting in the chest or face, often followed by sweating and sometimes a chill afterwards. They can last anywhere from a few seconds to several minutes and vary hugely in frequency.

3. Night sweats

Hot flushes that happen while you are asleep. They can be severe enough to wake you, or you might only notice damp sheets in the morning.

4. Sleep disturbances

Difficulty falling asleep, staying asleep, or waking far too early. This is not always linked to night sweats. It can also be driven by hormonal changes affecting sleep itself.

5. Mood changes

Irritability, anxiety, low mood, or finding that your emotional threshold is lower than usual. Hormones, disrupted sleep, and the broader life pressures many women face in their 40s all play a combined role. It is not in your head, it is a real physiological response.

6. Brain fog

Forgetting words mid-sentence, losing your train of thought, feeling mentally slower or less sharp than usual. This is one of the symptoms women often find most distressing, and one of the least talked about. It typically improves after menopause.

7. Weight changes and shifts in body composition

Many women notice weight gain around the abdomen during perimenopause, even without significant changes to diet or exercise. Muscle mass may decline and metabolism can slow.

8. Vaginal dryness and changes in libido

Lower oestrogen can lead to vaginal dryness, discomfort during sex, and changes in sexual drive. These symptoms often continue into menopause, but they are very treatable, often with low-dose vaginal oestrogen, which carries minimal systemic risk.

9. Bladder changes

More frequent urination, urgency, or a tendency toward urinary tract infections. Oestrogen helps maintain the tissue of the bladder and urethra, so as levels drop, changes in this area are common.

10. Joint stiffness and muscle aches

Some women notice new joint pain or stiffness during perimenopause, particularly in the morning. The link to oestrogen is still being studied, but it is a commonly reported symptom.

11. Changes to hair and skin

Hair may become finer or shed more, and skin may feel drier or less elastic. These changes tend to be gradual rather than sudden.

Early perimenopause versus late perimenopause

Yes, there is a difference, and it matters. The symptom picture can shift quite significantly as you move through the transition.

Early perimenopause is often characterised by symptoms associated with fluctuating and sometimes elevated oestrogen: heavier periods, breast tenderness, headaches, and bloating. Your cycles may become shorter and more frequent before they start to space out.

Late perimenopause, the stage closest to your final period, tends to involve more of the low-oestrogen symptoms: hot flushes, night sweats, vaginal dryness, and sleep disruption. Cycles become less frequent, with gaps of 60 days or more between periods a common marker.

This is one reason the same symptom in two different women might reflect very different hormonal states. It is also why blood tests, which give a snapshot of one moment, are not reliable for diagnosing perimenopause. In Australia, for women over 45 with typical symptoms and irregular periods, a clinical diagnosis based on your history is standard practice. You do not need a blood test to confirm it.

Perimenopause and your mental health

This deserves its own section, because it is consistently underestimated. The hormonal fluctuations of perimenopause genuinely affect mood, anxiety, and emotional resilience, not as a side effect but as a direct physiological response. Oestrogen plays a role in serotonin regulation, so when oestrogen fluctuates, your emotional baseline can shift with it.

Women with a history of anxiety, depression, or premenstrual mood changes tend to be more sensitive to these shifts, but even women who have never experienced significant mental health challenges can find themselves struggling in unfamiliar ways. This is not a weakness, and it is not just stress. It deserves to be treated as seriously as any other symptom, because the right support, whether hormonal, psychological, or both, can make a real difference. Our guide to menopause, mood and anxiety covers this in more depth.

If mood changes are significantly affecting your daily life, relationships, or work, mention it specifically to your doctor rather than burying it at the end of a list. It is often one of the most treatable aspects of perimenopause.

Practical things that actually help

You do not need an extreme overhaul. Small, consistent changes in a few key areas tend to have a more sustainable impact than doing everything at once and burning out.

Sleep. Prioritising sleep is arguably the highest-leverage thing you can do, because poor sleep amplifies almost every other symptom: mood, concentration, hot flush intensity, and appetite. A cool, dark room, a consistent sleep and wake time, and reducing alcohol are all worth trying.

Movement. Strength training twice a week helps preserve muscle and bone density, both of which decline with falling oestrogen. It does not need to be intense. Consistent matters more than hard. Adding some cardio for heart health and yoga or Pilates for flexibility and stress rounds out a strong foundation.

Nutrition. A diet built around whole foods, adequate protein, and calcium-rich sources, with limited ultra-processed food, gives your body a good baseline. Staying well hydrated can also help reduce the intensity of hot flushes for some women.

Stress. Chronic stress raises cortisol, which in turn worsens hormonal fluctuations. Even ten minutes a day of something that genuinely quiets your nervous system, whether walking, meditation, or journaling, is worth building into your routine.

Medical treatment options

If your symptoms are disrupting your sleep, work, relationships, or sense of wellbeing, that is enough reason to seek proper medical support. You do not have to reach a certain threshold of suffering before it counts.

Menopausal hormone therapy (MHT). MHT, formerly called HRT, is the most effective treatment for hot flushes and night sweats, and it also helps with sleep and vaginal symptoms. For some women it can ease low mood tied to the menopause transition, though it is not a first-line treatment for major depression, and its role for anxiety specifically is less well established. Modern evidence shows it is safe for most healthy women under 60 who are within ten years of menopause, and the risks and benefits depend on your individual health history. Our guide to MHT in Australia covers this in full.

Non-hormonal medications. Certain antidepressants, blood pressure medications, and other options can reduce hot flush frequency and intensity for women who are not suited to, or do not want, MHT.

Vaginal oestrogen. This is low-dose, local oestrogen applied directly to vaginal tissue. It is highly effective for dryness, discomfort during sex, and bladder symptoms, and carries very minimal systemic absorption. It is often appropriate even for women who cannot use systemic MHT.

Bone health. Oestrogen plays a significant role in maintaining bone density, and the perimenopausal years mark the beginning of accelerated bone loss. It is worth discussing your bone health with your doctor, particularly if you have risk factors for osteoporosis.

The right treatment plan is individual. A GP with a specific interest in women’s health, or a menopause specialist, will give you a more tailored conversation than a standard appointment allows. You can browse menopause-informed GPs in our directory.

Can you still get pregnant during perimenopause?

Yes, and this surprises many women. As long as you are still having periods, you are still ovulating, even if irregularly, which means pregnancy is possible. Fertility is significantly reduced in your 40s, but it has not gone to zero.

If you do not want to become pregnant, continue using contraception until you have had 12 consecutive months without a period if you are over 50, or 24 months without a period if you are under 50. MHT is not a contraceptive.

When to see a doctor

You do not have to wait until symptoms become severe. If you are noticing changes that affect your sleep, mood, work, or relationships, or you are simply not sure whether what you are experiencing is perimenopause, that is reason enough to make an appointment.

Some symptoms warrant more prompt attention and are not typical of perimenopause:

• Very heavy bleeding, or bleeding that soaks through a pad or tampon every hour or two
• Bleeding after sex
• Bleeding after you have already gone 12 months without a period
• Severe or sudden mood changes, including depression
• Chest pain, significant shortness of breath, or severe headaches

For everything else, the irregular cycles, the hot flushes, the brain fog, the mood shifts, you deserve a doctor who takes these seriously and works with you on a plan. If you are not getting that, it is okay to look elsewhere. Our Melbourne directory is a good starting point if you are searching for a women’s health GP or specialist.

A note on mindset

Perimenopause is routinely framed as a decline. It is not. It is a transition, a significant one, but not a one-way door into feeling worse. Many women find that having actual answers about what is happening in their body is itself a relief. The symptoms that felt random suddenly make sense, and once you understand what is driving them, you have real options.

You are not imagining it, and you do not have to just push through. For more on what comes next, read our guide to menopause treatment and relief in Australia. The Australasian Menopause Society also publishes reliable patient information.

Common questions

What are the first signs of perimenopause?
The first signs are typically changes to your menstrual cycle: irregular timing, heavier or lighter flow, or cycles shorter or longer than your usual pattern. This is usually followed by sleep changes, mood shifts, and in some women, early hot flushes or night sweats.

How do I know if I am in perimenopause?
Look for a change in your cycle alongside symptoms such as hot flushes, night sweats, sleep disruption, mood changes, and brain fog. Blood tests are not reliable for diagnosing perimenopause in women over 45. A clinical diagnosis based on your symptoms and cycle history is standard practice in Australia.

What age does perimenopause start in Australia?
Usually the mid-to-late 40s, though some women notice changes in their late 30s. The average age of menopause, the final period, is 51 to 52.

How long does perimenopause last?
On average four to six years, but it can range from a few months to a full decade. There is no way to predict in advance how long your transition will take.

Is perimenopause the same as menopause?
No. Menopause is a specific point in time, confirmed after 12 consecutive months without a period. Perimenopause is the transition leading up to that point. The two terms are often used interchangeably in conversation, but they refer to different stages.

Author: Sharryn Ludlow

Sharryn Ludlow is an Australian founder and strategy-and-operations practitioner. She is the founder of Menopause Resource Hub (AU), a curated directory helping women find menopause-informed support. Sharryn has worked across travel operations, group logistics, and project support for over 20 years, and is known for a direct, grounded style that cuts through noise and focuses on what works.